A record-breaking heat wave out West shows no signs of letting up for the rest of the week.

Excessive heat warnings remain in effect on Tuesday, as heat advisories cover the desert Southwest into Southern California and run north to the Pacific Northwest.

Daytime high temperatures will reach over 110 degrees Fahrenheit, or greater, in a number of locations.

BLISTERING HEAT ROASTS WEST WITH WIDESPREAD STORMS, TROPICS ACTIVE HEADING INTO HEART OF HURRICANE SEASON

According to the National Weather Service (NWS), nearly 42 million Americans are under warnings, while another 8.8 million are under advisories.

Forecast high temperatures for Tuesday, Aug. 18, 2020.

Forecast high temperatures for Tuesday, Aug. 18, 2020.

While afternoon highs are slightly cooler by late week, most of the West will see very little relief this week as temperatures remain well above average.

LIGHTNING FROM RARE 'VIOLENT' THUNDERSTORMS IN CALIFORNIA SPARKS DOZENS OF WILDFIRES ACROSS BAY AREA

The prolonged high temperatures are testing utilities in California, where the state's power grid operators avoided a third day of rolling blackouts on Monday but are keeping a wary eye on the thermometer.

Heat warnings and advisories for Tuesday, Aug. 18, 2020.

Heat warnings and advisories for Tuesday, Aug. 18, 2020. (Fox News)

Continued temperatures in the triple digits have kept the threat of outages high for the remainder of the week.

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The record heat across the West, including in Death Valley, which recorded 130 degrees on Sunday, is also bringing an increased risk of wildfires.

Firefighters in California scrambled Monday to contain multiple blazes, sparked by widespread lightning strikes throughout the region, as a statewide heat wave continues.

Firefighters in California scrambled Monday to contain multiple blazes, sparked by widespread lightning strikes throughout the region, as a statewide heat wave continues. (AP Photo/Noah Berger)

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